Climate change is a mysterious and ongoing threat that seeps into the depths of the oceans and seas around the world, and the Arabian Gulf region is no exception to this sad reality, but have things reached the point of catastrophe?

While the effects of climate change are evident on life above the Earth's surface, the state of life beneath the water's surface remains a mystery due to global warming, particularly given the abundance of biodiversity in the marine environment and unexplored areas. Nevertheless, scientists are striving to explore those deep depths and study the changes they undergo due to climate change.

Challenges

Scientists find it very difficult to monitor the sudden changes in ecosystems due to climate change, because studies usually shed light on short-term changes in marine biological communities, and obtaining information on long-term environmental drivers that contribute to shaping deep-sea ecosystems is challenging.

This prompted an international research group to examine fossil records and go back about 500,000 years to conduct a study shedding light on how the deep-sea ecosystems of the Southern Ocean evolved and how changes in temperature and food inputs affected the formation of these systems. The journal "Current Biology" published the study on December 19, 2024.

Backwards

Researchers used fossils extracted from sediment cores that extend back 500,000 years, which helps them understand long-term changes in light of the temperature fluctuations the Earth has experienced over those years. On the other hand, they seek to understand the impact of changes in food inputs on the deep marine environment.

Due to the minor temperature changes at depth compared to the surface's direct exposure to heat, researchers specifically focused on these two factors. This means that deep-sea organisms are more sensitive to temperature changes. As for food inputs, deep-sea organisms typically receive nourishment from dead plankton's organic remains that sink to the depths. Rising and fluctuating temperatures affect the source of these organic materials at the surface, resulting in changes in food inputs for deep-sea marine systems.

Researchers concluded that global warming resulting from human activities may weaken the global deep water circulation that starts in the Atlantic Ocean, passes through the Southern Ocean, and then reaches the Pacific Ocean. This, in turn, negatively affects temperatures and food inputs in the depths, leading to a decline in biodiversity in the deep seas of the Southern Ocean.